Electromechanical compound brake.



A. SUNDH.

ELEGTROMEGHANICAL COMPOUND BRAKE.

APPLIOATION FILED FEB. 15, 1906.

979,720. Patented Dec.27,1910.

ATTORNEY THE Ncmzfs PETERS 50., wAsnmuroN, n. c.

AUGUST SUNDH, OF YONKERS, NEW YORK, ASSIGN-OR TO OTIS ELEVATOR COMPANY,OF JERSEY CITY, NEW JERSEY, A CORPORATION OF NEW JERSEY.

ELECTROMECHANIOAL COMPOUND BRAKE.

Specification of Letters Patent.

Patented Dec. 27, 1910.

Application filed February 15, 1906. Serial No. 301,182.

To all whom "it may concern:

Be it known that I, AUGUST SUNDIYI, a citizen of the United States,residing at Yonkers, in the county of VVestchester and State of NewYork, have invented a new and useful Improvement in ElectromechanicalCompound Brakes, of which the following is'a specification.

My invention relates to brake apparatus, and is an improvement on thatshown in my pending application, S. No. 240,613, filed January 11th,1905, for an improvement in elevator brakes. It is particularly adaptedto electric motors, which are used for driving elevators.

One of the objects of my invention is the provision of a plurality ofpairs of brake shoes, all applied to the exterior surface of thecylindrical portion of a pulley secured to the motor shaft and one pairof said brake-shoes operating mechanism to apply the other pair.

A further object of my invention is the provision of independentlymounted and interconnected pairs of brake-shoes applied to the exteriorsurface of a brakepulley.

Another object of my invention is to provide a retarding device appliedto the eX- terior of a brake pulley and connections to an additionalretarding device similarly applied, so that upon the application of oneretarding device its rotary force received from the motor will betransmitted to the other rotary device.

Other objects of my invention will appear hereinafter, a novelcombination of elements being pointed out in the claim.

In the accompanying drawings, Figure 1 represents an electric motor withmy improved brake apparatus applied thereto; Fig. 2 is a sectional viewof Fig. 1, taken on the line aa, looking in the direction of the arrows;Fig. 3 represents a section of Fig. 1, taken on the line bb,' Fig. 4 isa sectional view of Fig. 4, taken on the line cc,' Fig. 5 is a plan viewof the left-hand portion of Fig. 1 to show the brake apparatus; Fig. 6is a plan sectional view of the leverage of the brake apparatus and Fig.7 is a view similar to Fig. 3, but illustrating the modification.

Referring to Fig. 1, M designates a motor which is herein shown as anelectric motor, but obviously the' same may be a motor driven by anyother power. This motor is supported in this instance on the bed plate 9by means of the standards 8, 8, and has a shaft S to one end of which isconnected the driving pulley I and to the other end of which is fastenedthe brake pulley 10. B designates a belt which connects the pulley P tothe parts to be driven, as for sample, elevator apparatus.

1, 1 are the bearings for the motor shaft; 2 designates a main lineswitch which connects the and mains to the motor leads 3 and 4; 7designates an electro-magnet solenoid which is connected across themotor mains by means of the wires 5 and 6.

Any suitable controlling apparatus may be used for starting and stoppingthe motor M. That is, any means for admittingand cutting off current onthe motor may be used and it should be noted that whenever the currentis cut off from the motor it is also cut off from the electro-magnetsolenoid 7. In the case of elevator apparatus, there could be a manualreversing switch in the car for controlling the electro-magnet reversingswitches so that the current would be admitted to the motor to operatethe same in the proper direction to move the car up or down as desired,in a well known manner.

12, 12 designate primary brake shoes which are arranged to be applied tothe brake pulley 10 by means of the springs 22, 22 acting on the leverarms 20, 20. These brake shoes are pivoted to the said arms 20, 20 at19, 19, respectively. To the upper portion of this rocking plate issecured the solenoid 7 which is provided with two movable cores 16, 16which are pivoted at their outer ends 17, 17 to the upper arms 21, 21 ofthe levers 18, 18-. The latter levers are pivoted to the rocking plate14 at 13, 13, respectively.

0n the bed plate 9 on the left-hand end thereof is secured a standard 28for supporting the bearing 29 in which is placed a short shaft 15 to theouter ends of which are secured the rocking plate 14 and the doublearmedlever 25, respectively. It will there fore be evident that when thesprings 22, 22 effect the application of the brake shoes 12, 12 to thepulley 10 while it is in motion the plate 14 will be rocked and with itthe lever 25. To the outer ends of this lever are connected thedepending links 26, 26. The

upper ends of these links are screw-threaded and provided with adjustingnuts 44, 44, while their lower ends are in this instance shown ringshaped, as at 37, 37, and passing through holes in the outer ends of thelevers 27, 27, respectively. Any suitable connection, however, may beused; that here shown being merely by way of illustration. The levers 27are pivoted at their central portion or at some point between their endsto the standards 30, 30, secured to the bed plate 9.

The inner ends oi the lever 27 converge toward each other and areloosely connected at 45 to the link 32, whose upper end has a slotconnection 33 with the bell crank levers 34, 34. These bell. cranklevers are pivoted at 35, 35 to the standards 36, 36 on the bed plate 9,and their upper arms carry the secondary brake shoes 11, 11, the latterbeing pivoted at 31, 31 to said upper arms. It is evident from aninspection of Fig. 1 that the secondary shoes 11, 11 are applied to theoutside of the pulley 10, as well as the primary shoes 12, 12, andalthough I have herein shown a single pulley 10, the double pulley maybe used, or any other modification made such as would occur to a personskilled in the art.

The operation of my invention is as follows: hen it is desired to startthe motor the current is admitted to the arn'iature and field of themotor as well as to the magnetic solenoid 7. The latter will thereupondraw inwardly its cores 16, 16 and move the shoes 12, 12 outwardlyagainst the action of the springs 22, 22, which are held in properposition by means of the connecting rod 23 and the adjusting nuts 24,24. The secondary shoes 11, 11 will at this time be also re leased byreason of the weighted lower portion of the rocking plate 14 holding thelever 25 in substantially horizontal position, as indicated in Fig. 2.If the connections be tween the secondary shoes 11, 11 and the lever 25are symmetrical, or nearly so, it is evident that when the rocking plate14 is in vertical position, as shown in Fig. 3, and the lever 25 inhorizontal position, the secondary shoes 11, 11 will be held oil" fromthe pulley 10, as shown in Fig. 4. The motor may now start and beoperated at any desired speed, depending upon the operation of the motorcontrolling apparatus (not shown). When it is desired to stop the motor,the current to the same is interrupted so that the electro-magnetsolenoid 7 will be deenen gized at the same time. This action will allowthe cores 16, 16 to be moved outwardly by means of the springs 22connecting on the lower ends of the lever arms 20, 20 which are pivotedat 13, 13 to the rocking plate 14. The primary brake shoes 12, 12 beingpivoted to the lever arms 20, 20 at 19, 19, respectively, will thus bemoved into engagement with the pulley 10. The motor armature at thistime is revolving by reason of its momentum, and also by reason of themomentum of the parts connected thereto, as for instance, elevator hoistapparatus, which in this instance may be connected to the motor by meansof the pulley and the belt. Upon the engagement of the primary brakeshoes 12, 12 with the momentum driven pulley 10, the latter will exert arotary force to rock the plate 14 in arc and predetermine the distanceto tilt the lever 25 in one direction or the other, depending upon thedirection of rotation of the motor armature.

Assuming that the motor armature is rotating in a clockwise direction,as viewed from the lefthand of Fig. 1, it is evident that when the brakeshoes 12, 12 are applied the rocking plates 14 will be moved also in aclockwise direction, and with it the doublearmed lever 25. The left-handvertical rod 26, as seen in Fig. 2, will therefore be moved upwardly,and with itthe outer end of the lever 27. The inner end of the lever 27which is connected to said rod 26 will be forced downwardly, and with itthe link 32 and the bell crank levers 34, 34 connected thereto. Thiswill, of course, move the secondary brake shoes 11, 11 against thepulley 10 and by proper designing of the leverages considerable forcemay be exerted by this secondary brake. It should furthermore be notedthat upon the application of the primary brakes there may be only smallretarding forcefor the reason that the plate 14 with the parts mountedthereon and connected thereto will be moved freely until the secondaryshoes are applied. Upon the application of the secondary brake, however,the rocking plate 14 is held stationary and the amount of braking forceof the primary shoes is determined by the tension of the springs 22, 22.The primary brake may be so ad usted that it alone will be sutlicient tostop the motor, but in order to more evenly distribute the strains ofthe brake apparatus and permit moving parts having greater momentum tobe stopped, it is preferable that thesecondary brake should be reliedupon for retarding the motor as well as the primary brake. The apparatusmay also be so arranged that by a comparatively small rotary forceimparted to the primary brake a much greater braking action may beproduced by the secondary brake.

In Fig. 7, I have illustrated a modification in that the primary brakemay be released mechanically, as by means of a rope or cable 43 passingaround the pulley 40, which is pivoted at 42 to the upper portion of therocking plate 14 in substantially the same position occupied by themagnetic solenoid 7 in Fig. 3. Instead of the core 16, 16 links 38, 38connect the lever arms 21, 21, respectively to the pulley 40; said linksbeing pivoted to said pulley at 41, 4:1. The pulley therefore acts as adouble-armed lever upon being rotated in an anti-clockwise direction tomove the levers 18, 18 about their fulcrums 13, 13 against the action ofthe brake applied springs 22, 22. This will, of course, move the brakeshoes 12, 12 out of engagement with the brake pulley 10. Since thesecondary brake shoes may be released when the motor is not running, theprimary brake should exert suflicient force to hold the motor and theparts connected thereto in stationary position. In some instances,however, upon the application of the primary brake and the consequentapplication of the secondary brake, the motor and the parts connectedthereto may be stopped so as to lift both the primary and secondarybrakes applied to hold said motor and connected parts in stationaryposition. In such case, upon the energization of the magnet solenoid 7or upon the rotation of the pulley 10 in an anti-clockwise direction,both brakes would evidently be released. The rope 43 illustrated in Fig.7, when the brake operation is used in connection with an elevator, maybe an operating rope running through and used in conjunction with themotor controlling apparatus for starting and stopping the elevator car.

Although, I have herein shown one form of my invention, I wish it to beunderstood that I do not desire to be limited to the exact details ofconstruction, for obvious modifications will occur to a person skilledin the art.

Having thus described my invention, What I claim and desire to secure byLetters Patent of the United States is:

In a compound brake, the combination with a brake pulley, of a rockplate, a primary brake carried by said rock plate, and associated withthe outside surface of said pulley, a secondary brake similarlyarranged, spring mechanism for effecting the application of said primarybrake, and a plurality of link and lever connections between said rockplate and said secondary brake.

In testimony whereof, I have signed my name to this specification in thepresence of two subscribing witnesses.

AUGUST SUNDI-I.

Vitnesses CHAS. M. NissnN, J. HALL KINsLnY.

